Generation of storage stability data for agricultural chemical products

Agricultural chemical products can undergo chemical and physical changes on storage. The rate at which these changes occur depends on the nature of the active constituent(s), the formulation type, the packaging and, notably, the storage conditions (temperature, light and humidity). The product remains fit for use as long as these changes have no adverse effects on application, biological performance, the safety of operators, consumers and the environment.

This guideline provides a comprehensive guide to the conduct of stability testing for agricultural chemical products. The APVMA stability testing guideline has been constructed to closely follow the Manual on the development and use of FAO and WHO specifications for pesticides (JMPS 2010) (FAO/WHO pesticide specifications).

1. Generating storage stability data

Storage stability data should be generated with the product stored in the proposed commercial packaging (or smaller packages of the same construction and material) under accelerated conditions and/or long-term testing at room temperature or under ambient warehouse conditions. However, it is recommended that you conduct long-term testing at 30 ˚C, which reflects Australian field conditions. After you have carried out these storage stability studies, you should supply the following information to the APVMA:

  • shelf-life specifications, with proposed limits for the content of active constituent and physical characteristics of the product within which the properties of the product will remain during its shelf life
  • actual test results, with full details of the methods used for each of the test parameters listed in the shelf-life specifications
  • stability of the packaging materials showing no significant deterioration, as interaction with the product can cause brittleness, softening, and corrosion.

The data you provide should support the claim that the formulated product will remain within specification for at least two years, when stored in its unopened original container, away from direct sunlight, at or above 25 ˚C. This should include a statement to the effect that the packaging is unaffected during the proposed shelf life.

A shorter shelf life may be approved where the data do not support a two-year shelf life. Some agricultural chemical products are subject to shorter shelf lives. For further information, see the separate guideline on date-controlled agricultural chemical products.

1.1. Shelf-life statement on the product label

It is a normal convention that information on storage stability (expiry date) is given on the product label only if the product cannot be stored for at least two years at or above 25 ˚C. The printed labels should include the date (month and year) of manufacture of the batch and relevant information on the conditions under which the product should be stored.

If the formulation has a shelf life of less than two years, the expiry date must also be included on the product label (for example, the ‘use-by date’ for date-controlled products). A list of date-controlled products is available in the Agricultural and Veterinary Chemicals Code Regulations 1995 (Agvet Code Regulations) and further information is available in the date-controlled agricultural chemical products guideline.

2. Design of stability testing trials

2.1. Size and number of batches

Stability testing should be conducted on laboratory-, pilot- or production-scale batches of the product (stability data generated on a batch size of less than 5 kilograms or 5 litres are normally not acceptable). The formulation should be the same as that proposed for registration in Australia. You should record and report the batch size, batch identity and date of manufacture of the batches used in the stability trials together with the stability data.

2.2. Storage conditions and duration

Storage stability programs may include accelerated or real-time tests, or both. Real-time testing is generally conducted for a product that may be unstable at high temperature (for example, a biological product) or a product that gives an uncertain conclusion under an accelerated test (for example, a hydroscopic product such as ammonium sulphate, which is prone to caking when exposed to moisture, should be subject to a real-time test or an anti-caking agent should be added into the product). For some formulations, studies at lower temperatures may be necessary due to the instability of the formulation at higher temperatures (this should be reflected in the recommended storage conditions). You should also test liquid formulations at low temperatures (0 ± 2 ˚C or lower).

2.3. Accelerated testing

Stability tests at elevated temperatures are designed to increase the rate of chemical degradation or physical change of a product. Testing is performed at elevated temperatures in an attempt to obtain information on the shelf life of a product in a relatively short time. Accelerated testing involves extrapolations from higher to lower temperatures and from shorter to longer storage periods.

The FAO/WHO pesticide specifications recommend testing of the relevant product parameters before and after storage at 54 ˚C for 14 days. However, for preparations that may not be stable at 54 ˚C for 14 days, the alternative times or temperatures listed in Table 1 may be used. An aerosol product may be tested at 40 ˚C for 8 weeks due to the unstable nature of the product at higher temperatures.

Table 1: Accelerated storage temperatures and duration of stability trials

Temperature

Duration

54 ˚C

14 days

45 ˚C

6 weeks

40 ˚C

8 weeks

Products that exhibit an adequate stability profile under any of these conditions are likely to be stable for two years under normal (at or above 25 ˚C) storage conditions.

2.4. Real-time testing

Data from an accelerated study can give a useful indication of a product’s stability, but products may pass this test and yet still be unstable on long-term storage. Therefore, it is recommended that you provide stability data generated at ambient temperatures over a period of two years (real-time testing). For example, if the proposed product has the ability to cake over time or is subject to contamination of bacterial or fungal growth, accelerated testing would not be suitable to demonstrate the product’s stability, but real-time testing would be appropriate.

Real-time testing is normally performed at or above 25 ˚C for at least two years at appropriate intervals. Depending on the formulation type and packaging material, testing under standardised relative humidity and light exposure conditions may also be recommended.

We recommend that you provide real-time data for date-controlled agricultural chemical products.

2.5. Cold-stability testing

Liquid formulations (capsule suspensions, emulsifiable concentrates, oil-in-water emulsions, micro- emulsions, soluble concentrates, suspension concentrates) may be adversely affected by storage at low temperatures. Storage at low temperatures may result in crystallisation of active constituent(s), significant changes in viscosity or phase separation of emulsions.

In some places in Australia, night temperatures regularly approach 0 ˚C or lower. Therefore, the liquid formulations should also be tested at 0 ±2 ˚C or lower for seven days. The effect of low temperatures on stability should be determined and reported according to Collaborative International Pesticide Analytical Council (CIPAC) method MT 39.3 (liquid formulations).

Stability data generated at low temperatures are not applicable if the product label contains a warning against exposure to low temperatures.

2.6. Test parameters

The stability profile of an agricultural chemical product is determined by monitoring a combination of chemical and physical properties during storage. Monitoring the content of active constituent alone is insufficient to make any reliable prediction about the stability of the product. On prolonged storage, a product may exhibit negligible decline in the concentration of active constituent, yet the important physical properties (for example, wettability or suspensibility) may have changed to such an extent that the performance of the product can be compromised.

This guideline includes relevant test parameters for each formulation type. We expect you to address all relevant parameters in a stability trial, in order to adequately demonstrate product stability. If certain parameters are not addressed, then you should provide a relevant scientific argument to explain why you did not test for those parameters. Note that the relevant test parameters have been derived from the FAO/WHO pesticide specifications. For formulation types not listed in this guideline, the APVMA accepts the testing parameters recommended in the FAO/WHO pesticide specifications.

2.7. Containers

The effect of the formulation on the primary pack and vice versa is important, and therefore the product should be packaged in the same containers (materials and pack size) that are proposed for the marketing of the final product. If the product is to be marketed only in containers in which stability testing would be impractical (for example, because they are too large), then stability trials in smaller containers of the same materials and construction may be used to extrapolate to the larger containers.

You should report the packaging materials, the size of the container, and the quantity of the product in the container used in stability trial.

Containers should be examined to ensure that no significant interaction with the formulation (affecting the stability or integrity of the packaging material) has taken place during storage.

2.8. Product in water-soluble bags

Effects on the physical characteristics of a product are known to occur when a product is packaged in water-soluble bags or sachets. Therefore, when this type of packaging is proposed, you should do relevant physical tests in the presence of the soluble bag material, in the same ratio as will occur in the spray tank or other application equipment.

In addition, testing of the dissolution characteristics of water-soluble bags should be carried out using CIPAC method MT 176. The dissolution time should be reported.

You should also examine leakage and/or effects of the formulation on water-soluble bags. Where multiple bags are to be packaged in a single container, you have to provide evidence that the integrity of the water-soluble packaging is not affected either by the opening and resealing of the outer pack or by moisture entering through routine use. This may be achieved by storing a multi-bag pack at 25 ˚C over a six-month period and periodically removing a water-soluble bag, until all bags have been removed. The integrity of the water-soluble bags should be examined on removal.

If the product is to be packaged in a water-soluble pack, the packaging material is treated as part of the formulation composition. Therefore, if the product is currently registered in some other packaging, a change to water-soluble packaging would require additional stability trials examining the product packaged in water-soluble bags.

2.9. Analytical methods

You should provide full details of the analytical methods used to monitor the product during stability trials, except where you have used collaboratively tested standard methods (CIPAC, Association of Official Analytical Chemists (AOAC), etc.) for the analysis, since these are regarded as validated and do not require full revalidation (for further details of the necessary degree of method validation see the separate guideline on validation of analytical methods. You should also provide details of all important operational parameters. These include:

  • instrumentation
  • sample preparation
  • method of extraction of the active constituent from the product
  • reference standards and reagents preparation
  • validation data
  • copies of representative chromatograms
  • representative calculations.

Analytical methods described in CIPAC handbooks and the AOAC manual for an agricultural active constituent and agricultural chemical product are legally recognised as the regulatory methods, and these procedures (if one is available) are used by the APVMA. We recommend that analytical methods described in official and recognised publications, such as CIPAC handbooks and AOAC, for a particular formulation be used, where available. However, you may propose alternative analytical methods in place of regulatory methods.

The results and interpretation of the measurement of physical properties are highly dependent on the analytical procedures used. We recommend that you use standard CIPAC or equivalent accepted methods to measure the physical properties of agricultural chemical products. If in-house company methods or other methods are used, then you should provide a full description of the procedure with the validation data.

2.10. Validation of analytical methods

2.10.1. Determination of active constituent content

You should provide validation data to confirm that the analytical procedures used in stability testing give reliable and accurate results. The type of validation data required is dependent on the analytical technique, but typically includes demonstration of linearity over a suitable concentration range, specificity, precision and accuracy (see the separate guideline on validation of analytical methods for further information).

Analytical methods described in official and recognised publications, such as CIPAC handbooks and the AOAC manual for pesticidal products are regarded as validated and do not require revalidation. However, the suitability of these methods should be verified under actual conditions of use; that is, the specificity and accuracy of the method should be demonstrated for the published method when applied to the relevant sample matrix and laboratory conditions.

2.10.2. Determination of physical properties

Validation of methods used to determine physical parameters will not be required, provided that CIPAC or equivalent accepted methods are used.

3. Technical characteristics of products

The data and/or testing parameters that the APVMA adopts are derived from the FAO/WHO pesticide specifications. You should describe and justify any divergences from these specifications in detail.

3.1. Appearance and physical state

These tests are performed visually and are described in qualitative terms such as solid, liquid, suspension etc.

3.1.1. Colour

You may use the following test methods to describe this parameter:

A visual description of colour is also acceptable.

3.1.2. Odour

This test is performed organoleptically and involves the use of descriptive terms (for example, thymol-like odour), characteristics of aromatic compounds (for example, garlic-like).

3.1.3. Acidity or alkalinity and pH

This test is recommended for any product where acidity or alkalinity and pH are relevant parameters for the quality of the product. Where relevant (that is, when the product is to be applied as an aqueous dilution), you should determine the pH of a one per cent aqueous dilution, emulsion or dispersion of the product and report this according to CIPAC method MT 75.3. A change in pH on storage can give an indication of instability of the active substance or product.

The acidity or alkalinity is determined by titration with standard acid or alkali according to CIPAC method MT 31.

3.1.4. Wettability

Wettability of solid products that are diluted for use (for example, wettable powders, water-soluble powders, water-soluble granules and water-dispersible granules) is determined to ensure the product is adequately wetted before use.

The wettability CIPAC method is: MT 53.3.

3.1.4.1. Acceptable limits for wettability

The wettability of a product is considered acceptable if there is complete wetting in one minute, without swirling.

If the product is outside these limits, then evidence should be submitted that demonstrates the product has acceptable dispersion in the spray tank or other application equipment.

3.1.5. Persistent foaming

Persistent foam is a measure of the amount of foam likely to be present in a spray tank or other application equipment following dilution of the product with water in accordance with the label instructions.

The CIPAC method for persistent foaming is: MT 47.1 or 47.2.

Although MT 47.2 was standardised for the determination of persistent foam in suspension concentrates, it is also applicable to other products that are dispersed in water.

3.1.5.1. Acceptable limits for persistent foaming

The following acceptable limits apply:

  • MT 47.1—max 25 mL foam after 1 min
  • MT 47.2—max 60 mL foam after 1 min.

3.1.6. Suspensibility

Suspensibility of water-dispersible products (for example, wettable powders, water-dispersible granules and suspension concentrates) is determined to demonstrate that a sufficient amount of the active substance is suspended in the spray liquid to give a satisfactory, homogeneous mixture during spraying.

The following CIPAC methods apply:

  • MT 15.1—wettable powders
  • MT 161—aqueous suspension concentrates
  • MT 168—water-dispersible granules
  • MT 177—water-dispersible powders
  • MT 184—formulations forming suspensions on dilution with water.

For the determination of suspensibility, chemical assay (active suspensibility) is the only fully reliable method to measure the mass of the active substance still in suspension. However, gravimetric determination (total suspensibility) or solvent extraction determination may be used on a routine basis, provided that these methods have been shown to give equivalent results to those of the chemical assay.

When the solvent extraction method is used, the product should be assayed using the same technique to allow comparison of the results.

Where there is more than one insoluble active substance present in the product, chemical assay (active suspensibility) is the only acceptable method.

The suspensibility test should be performed at the highest and lowest dilutions recommended on the product label.

3.1.6.1. Acceptable limits for suspensibility
  • The mean measured active suspensibility should not be less than 60 per cent and not greater than 105 per cent.

If a product is outside these limits, you should submit evidence to demonstrate that the product is homogeneous on application through appropriate application equipment (for example, through determination of active content in the spray at the beginning, middle and end of the spraying operation).

3.1.7. Spontaneity of dispersion (suspension stability)

The spontaneity of dispersion of water-dispersible products (for example, water-dispersible granules and suspension concentrates) is determined to show the product is easily and rapidly dispersed when diluted with water.

The following CIPAC methods apply:

  • MT 160—suspension concentrates
  • MT 174—water-dispersible granules.

Chemical assay is the only reliable means to measure the mass of the active substance in suspension. However, you may use gravimetric determination or solvent extraction determination on a routine basis, provided you can show that these methods give equivalent results to those of the chemical assay.

When using the solvent extraction method, you should assay the product using the same technique, to allow comparison of the results.

Where there is more than one insoluble active substance present in the product, chemical assay is the only acceptable method.

3.1.7.1. Acceptable limits
  • The mean measured active suspensibility or dispersibility should not be less than 60 per cent and not greater than 105 per cent.

Where a product is outside these limits, you should submit evidence to demonstrate that the product is homogeneous on application through appropriate application equipment.

3.1.8. Dilution stability

Dilution stability is determined to ensure water-soluble products dissolve readily and, when diluted, produce stable solutions without precipitation, flocculation, etc.

The following CIPAC methods apply:

  • MT 179—degree of dissolution and solution stability
  • MT 41—dilution stability of herbicide aqueous solutions.
3.1.8.1. Acceptable limits for dilution stability
  • MT 41—‘trace’ of sediment after 30 minutes
  • MT 179—max 2 per cent on 75 μm sieve.

Where a product is outside these limits, you should submit evidence that shows the material separated will not block nozzles in application equipment.

3.1.9. Dry sieve test

The dry sieve test is designed to determine the particle size distribution of dustable powders and granules that are intended for direct application, to ensure acceptable application.

The following CIPAC methods apply:

  • MT 59.1 dusts
  • MT 59.2 granular formulations
  • MT 170  water-dispersible granules.

For dustable powders, if 5 per cent or more of the product is retained on a 75 micrometre (μm) sieve, the active content of material remaining on the sieve should be determined to demonstrate there was no separation of the active substance from the carrier.

3.1.9.1. Acceptable limits for the dry sieve test

Maximum 5 per cent is retained on a 75 µm sieve (dustable powders) not more than (0.005 times the active content in grams per kilogram [g/kg]) per cent should be present as the active in the residues on the sieve.

3.1.10. Wet sieve test

For water-dispersible products, a wet sieve test should be conducted. Wet sieve analysis determines the quantity of particles in a formulation collected on a screen after dilution in water.

The following CIPAC method applies:

  • MT 185—wet sieve test, a revision of methods MT 59.3 and MT 167.

The residue remaining on a sieve is determined after dispersion to ensure that no unacceptable residue remains, which can cause blockage of nozzles in application equipment.

This test is applicable to wettable powders, suspension concentrates, water-dispersible granules, aqueous capsule suspensions, dispersible concentrates, suspo-emulsions, water-soluble granules and water-soluble powders.

3.1.10.1. Acceptable limits for the wet sieve test
  • Maximum 2 per cent retained on a 75 µm sieve.

Where a product is outside these limits, you should submit evidence that show the product may be satisfactorily applied through appropriate application equipment with no blockages.

3.1.11. Particle size distribution

You should determine the nominal size range for solid materials for direct application (for example, dustable powders and granules) and solid materials for dispersion in water (for example, wettable powder and granules). The data are used to assess if an acceptable proportion of the product is within an appropriate size range.

The following methods apply:

  • CIPAC MT 170—water-dispersible granules
  • CIPAC MT 187—particle size analysis by laser diffraction
  • OECD method 110—powders or dusts.

3.1.12. Dust content

You should determine the dust content of solid preparations to ensure the risk to operators is acceptable and to determine the potential for blockage of application equipment.

The following methods apply:

  • CIPAC method MT 171—granular products
  • OECD method 110—powders or dusts.

MT 171 describes two methods for the determination of dustiness, but the gravimetric method is regarded as the reference method.

3.1.12.1. Acceptable limits for dust content

If 1 per cent, by weight, of the preparation has a particle size of less than 50 µm, you should also provide inhalation toxicity data.

3.1.13. Emulsifiability, re-emulsifiability and emulsion stability

For products that form emulsions, data on emulsifiability, emulsion stability and re-emulsifiability are used to determine whether a product forms and maintains a stable emulsion.

The following CIPAC methods apply:

  • MT 36.1—5 per cent dilution
  • MT 36.2—1 per cent dilution
  • MT 36.3—emulsion characteristics and re-emulsification properties
  • MT 173—0.1–2 per cent dilution.

MT 36.1 is designed to be conducted over a 24-hour period. If no separation of cream or oil is observed after two hours, then no further testing is required. However, if separation is observed, you should do the 24-hour test.

For dilute emulsion, MT 173 is the preferred method. However, MT 36.1 may be used as a screening method. If no separation of the 5 per cent dilution is seen after two hours, then no further testing is required. The test should be conducted in CIPAC waters A and D.

3.1.13.1. Acceptable limits for emulsifiability, re-emulsifiability and emulsion stability
  • MT 36.1—maximum 2 mL cream, trace of oil after 30 minutes; if any separation is observed, re-emulsification should be complete after 24 hours
  • MT 173—min 98 per cent after 4 hours; max 102 per cent after 4 hours.

If a product is outside these limits, you should submit evidence that shows the product remains homogeneous when applied through appropriate application equipment. If more than a trace of oil separates, you should consider re-formulation of the product.

3.1.14. Dispersion stability of suspo-emulsions

Data should be provided to ensure that a sufficient amount of active constituent is homogeneously dispersed in suspension and emulsion in the spray liquid, to give a satisfactory and effective mixture during spraying.

The following CIPAC method applies:

  • MT 180.
3.1.14.1. Acceptable limits for stability of suspo-emulsions
  • Maximum 2 mL cream, trace of oil after 30 min. If any separation is observed, re-emulsification should be complete after 24 hours.

If a product is outside these limits, you should submit evidence that shows the product remains homogeneous when applied through appropriate application equipment. If more than a trace of oil separates, you should consider re-formulation of the product.

3.1.15. Pourability (risibility) of suspension concentrates

Data are required to demonstrate that the user can make use of the maximum amount of the product in the container and that an excessive amount of the material does not remain in the container. This test should be conducted with suspension concentrates, capsule suspensions and suspo-emulsions.

The following CIPAC methods apply:

  • MT 148
  • MT 148.1 (revised method).
3.1.15.1. Acceptable limits for pourability (risibility) of suspension concentrates

Maximum 5 per cent residue; maximum 0.25 per cent rinsed residue.

If a product is outside these limits, you should submit evidence on the residue remaining in the commercial pack following recommended rinsing procedures.

3.1.16. Attrition and friability

Attrition is defined as the wearing away of the surface of a granule by friction or impact, particularly by granule-to-granule interaction.

Friability is defined as the tendency of the granule to crumble, breaking down to smaller particles.

Data are required to determine whether a granular material is robust under normal conditions of use and transport.

The following CIPAC methods apply:

  • MT 178—measures attrition resistance of granules
  • MT 178.2—measures attrition resistance of dispersible granules.
3.1.16.1. Acceptable limits for attrition and friability

If the material has an attrition resistance of less than 98 per cent, evidence is required that the material may be satisfactorily applied through application equipment.

3.1.17. Viscosity

The viscosity of a fluid is the property that determines the resistance offered to a shearing force under laminar flow conditions; for example, resistance to slow stirring, or to flow through a capillary or narrow channel.

The kinematic viscosity of liquid formulation for direct application (ultra-low-volume products) should be determined. For Newtonian fluid, the viscosity at any shear rate should be conducted; whereas, if the product is a non-Newtonian fluid (for example, a non-drip paint), you should provide at least two different viscosity values at different shear rates.

The following CIPAC methods apply:

  • MT 22
  • MT 114.

3.1.18. Flowability

The following methods apply:

  • CIPAC method MT 44
  • OECD method MT 172.
3.1.18.1. Acceptable limits for flowability

The sample should flow through the sieve after a maximum of five liftings.

3.1.19. Dissolution rate of water-soluble bags

The dissolution rate of water-soluble bags should be carried out to demonstrate that particles of water-soluble material will not block nozzles of application equipment.

The following CIPAC method applies:

  • MT 176.
3.1.19.1. Acceptable limits for the dissolution rate of water-soluble bags

The dissolution rate of water-soluble bags is 30 seconds.

3.1.20. Disintegration time and degree of dispersion or dissolution

Data are required to demonstrate that soluble or dispersible tablets disintegrate rapidly on addition to water and that the formulation is readily dispersed or dissolved.

3.2. Parameters to be tested in stability trials

In addition to appearance and content of active constituent, the relevant physical chemical properties of each formulation type should be monitored before and after storage where applicable. For the following shelf-life specifications, the physical properties mentioned in the FAO/WHO pesticide specifications have been selected as they are applicable to the given formulation type. The APVMA will update the relevant test parameters for the additional formulation types listed in the Formulation Types guideline.

International codes used below are based on the Catalogue of pesticide formulation types and international coding system (CropLife International 2008). Individual CIPAC MT test parameters are listed with each individual formulation type within this document.

In this guideline CIPAC MT methods are referenced as the appropriate MT number (for example, MT 59.1 = CIPAC MT 59.1).

Table 2: Dustable powders (DP)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Dry sieve test

MT 59.1

Packaging stability

Observation of packaging stability

(Note: There should be no caking in the pack on storage.)

Table 3: Powders for dry seed treatment (DS)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Dry sieve test

MT 59.1

Particle size distribution

OECD 110

Adhesion to seeds

Appropriate validated method

Packaging stability

Observation of packaging stability

Table 4: Granules (GR)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Pour and bulk density

MT 186

Particle size distribution

MT 58.3

Dust content

MT 171

Friability and attrition characteristics

MT 178

Release rate of active constituent

Suitable validated method

Packaging stability

Observation of packaging stability (Note: There should be no loss of granule integrity or caking on storage.)

Table 5: Tablets for direct application (DT)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Tablet integrity

Visual observation
(Note: No broken tablets.)

Tablet hardness

No CIPAC method

Degree of attrition

MT 193

Packaging stability

Observation of packaging stability

Table 6: Wettable powders (WP)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Wet sieve test*

MT 185

Suspensibility*

MT 184

Wettability*

MT 53.3

Persistent foam*

MT 47.2

Dissolution of water-soluble bags

MT 176
(Note: Only if the product is packaged in a sealed water-soluble bag.)

Packaging stability

Observation of packaging stability (Note: There should be no caking in the pack on storage.)

* If the product is packaged in a water-soluble bag, you should do the wet sieve test, suspensibility, wettability test and persistent foam test using a solution of the product and water-soluble bag in the same ratio as in the recommended application.

Table 7: Water-dispersible powders for slurry seed treatments (WS)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Wet sieve test

MT 185

Wettability

MT 53.3

Persistent foam

MT 47.2

Dissolution of water-soluble bags

MT 176

(Note: Only if the product is packaged in a sealed water-soluble bag.)

Packaging stability

Observation of packaging stability

Table 8: Water-dispersible granules (WG)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Wet sieve test*

MT 185

Degree of dispersion

MT 174

Suspensibility*

MT 184

Wettability*

MT 53.3

Persistent foam*

MT 47.2

Dust content

MT 171

Flowability

MT 172

Dissolution of water-soluble bags

MT 176

(Note: Only if the product is packaged in a sealed water-soluble bag.)

Attrition resistance

MT 178.2

Packaging stability

Observation of packaging stability

(Note: There should be no caking in the pack on storage.)

* If the product is packaged in a water-soluble bag, you should do the wet sieve test, suspensibility, wettability test and persistent foam test using a solution of the product and water-soluble bag in the same ratio as in the recommended application.

Table 9: Water-dispersible tablets (WT)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Tablet integrity

Visual observation

(Note: No broken tablets.)

Suspensibility

MT 184

Disintegration time

Appropriate method

Wet sieve test

MT 185

Persistent foam

MT 47.2

Packaging stability

Observation of packaging stability

Table 10: Emulsifiable granules (EG)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Wettability

MT 53.3

Dispersion stability

MT 180

Wet sieve test

MT 185

Dustiness

MT 171

Persistent foam

MT 47.2

Packaging stability

Observation of packaging stability

Table 11: Emulsifiable powders (EP)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Wettability

MT 53.3

Dispersion stability

MT 180

Wet sieve test

MT 185

Persistent foam

MT 47.2

Packaging stability

Observation of packaging stability

Table 12: Water-soluble powders (SP)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Persistent foam*

MT 47.2

Wettability*

MT 53.3

Degree of dissolution and solution stability

MT 179

Dissolution of water-soluble bags

MT 176

(Note: Only required if the product is packaged in a sealed water-soluble bag.)

Packaging stability

Observation of packaging stability

(Note: There should be no caking in the pack on storage.)

* If the product is packaged in a water-soluble bag, you should do the wettability, degree of dissolution, solution stability test and persistent foam test using a solution of the product and water-soluble bag in the same ratio as in the recommended application.

Table 13: Water-soluble powders for seed treatment (SS)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Degree of dissolution and solution stability

MT 179

Packaging stability

Observation of packaging stability

(Note: There should be no caking in the pack on storage.)

Table 14: Water-soluble tablets (ST)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Tablet integrity

Visual observation

(Note: No broken tablets.)

Degree of dissolution and solution stability

MT 179

Wet sieve test

MT 185

Disintegration time

Appropriate method

Persistent foam

MT 47.2

Degree of attrition

MT 193

Packaging stability

Observation of packaging stability

Table 15: Soluble concentrates (SL)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Solution stability

MT 41

Persistent foam

MT 47.2

Low temperature stability

MT 39.3

Packaging stability

Observation of packaging stability

Table 16: Solutions for seed treatment (LS)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Solution stability

MT 41

Low temperature stability

MT 39.3

Packaging stability

Observation of packaging stability

Table 17: Oil miscible liquids (OL)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity/alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Miscibility with hydrocarbon oil

MT 23

Low temperature stability

MT 39.3

Packaging stability

Observation of packaging stability

Table 18: Ultra low volume liquids (UL)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Low temperature stability

MT 39.3

Kinematic viscosity

MT 22, OECD 114

Packaging stability

Observation of packaging stability

Table 19: Emulsifiable concentrates (EC)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Emulsion characteristics

MT 36.1, MT 36.2, MT 36.3, MT 173 or MT 183

Persistent foam

MT 47.2

Low temperature stability

MT 39.3

Packaging stability

Observation of packaging stability

Table 20: Dispersible concentrates (DC)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Dispersion stability

MT 180

Wet sieve test

MT 185

Persistent foam

MT 47.2

Low temperature stability

MT 39.3

Packaging stability

Observation of packaging stability

Table 21: Emulsions, oil in water (EW)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Emulsion characteristics

MT 36.1, MT 36.2, MT 36.3, MT 173 or MT 183

Pourability

MT 148.1

Persistent foam

MT 47.2

Viscosity

MT 192

Low temperature stability

MT 39.3

Packaging stability

Observation of packaging stability

Table 22: Emulsions for seed treatment (ES)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Emulsion stability on dilution with water

Appropriate method

Persistent foam

MT 47.2

Low temperature stability

MT 39.3

Packaging stability

Observation of packaging stability

Table 23: Micro-emulsions (ME)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Emulsion characteristics

MT 36.1, MT 36.2, MT 36.3, MT 173

Persistent foam

MT 47.2

Low temperature stability

MT 39.3

Packaging stability

Observation of packaging stability

Table 24: Suspo-emulsions (SE)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Dispersion stability

MT 180

Pourability

MT 148.1

Wet sieve test

MT 185

Persistent foam

MT 47.2

Low temperature stability

MT 39.3

Packaging stability

Observation of packaging stability

Table 25: Suspension concentrates (SC)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Pourability

MT 148

Suspensibility

MT 184

Spontaneity of dispersion

MT 160

Wet sieve test

MT 185

Persistent foam

MT 47.2

Low temperature stability

MT 39.3

Packaging stability

Observation of packaging stability

Table 26: Suspension concentrates for seed treatment (FS)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Pourability

MT 148

Suspensibility

MT 184

Wet sieve test

MT 185

Persistent foam

MT 47.2

Low temperature stability

MT 39.3

Packaging stability

Observation of packaging stability

Table 27: Capsule suspensions (CS)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Pourability

MT 148

Suspensibility

MT 184

Spontaneity of dispersion

MT 160

Wet sieve test

MT 185

Persistent foam

MT 47.2

Freeze or thaw stability

No CIPAC method

(Note: Testing of stability parameters [acidity, alkalinity or pH range; pourability; suspensibility; spontaneity of dispersion; wet sieve test] required after freeze or thaw cycle)

Packaging stability

Observation of packaging stability

Table 28: Oil-based suspension concentrates (OD)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Acidity or alkalinity or pH

MT 31 or MT 191 or pH range (MT 75.3)

Pourability

MT 148

Dispersion stability

MT 180

Wet sieve test

MT 185

Persistent foam

MT 47.2

Low temperature stability

MT 39.3

Packaging stability

Observation of packaging stability

Table 29: Water-soluble gels (GW)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Dilution stability*

MT 41

Packaging stability

Observation of packaging stability

* Only required if the preparation is to be dissolved in water.

Table 30: Mosquito coils (MC)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Average weight of coils

No CIPAC method

Burning time

No CIPAC method

Strength of coil

No CIPAC method

Packaging stability

Observation of packaging stability

Table 31: Vaporiser mats (MV)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Packaging stability

Observation of packaging stability

Table 32: Liquid vaporisers (LV)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Packaging stability

Observation of packaging stability

(Note: No corrosion.)

Table 33: Baits (including grain bait [AB], block bait [BB], granular bait [GB], ready-to-use bait [RB] and plate bait [PB])

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Evidence of retention of biological efficacy may be acceptable

Packaging stability

Observation of packaging stability and integrity

Table 34: Products to be applied as smokes (including smoke tins [FD], smoke candles [FK], smoke cartridge [FP], smoke rodlet [FR], smoke tablet [FT], smoke generators [FU] and smoke pellets [FW])

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Burning time

No CIPAC method

Evidence of combustibility

No CIPAC method

Packaging stability

No CIPAC method

Table 35: Aerosol dispensers (AE)

Recommended test parameters

Relevant CIPAC method

Appearance (physical state, colour, odour)

No CIPAC method

Active constituent content

Appropriate validated method

Internal pressure

No CIPAC method

Discharge rate

No CIPAC method

pH

No CIPAC method

Clogging of aerosol dispenser valves

No CIPAC method

Spray pattern

No CIPAC method

Packaging stability

Observation of packaging stability

(Note: No corrosion.)

4. References

Association of Official Analytical Chemists, Official methods of analysis of AOAC International, AOAC International, Arlington VA, United States.

ASTM International Annual book of ASTM standards; American Society for Testing and Materials, Philadelphia PA, United States. http://www.astm.org/BOOKSTORE/BOS/index.html

CIPAC, CIPAC Handbooks, Black Bear Press, Cambridge, United Kingdom.

CropLife International 2008, Catalogue of pesticide formulation types and international coding system. Technical Monograph No. 2, 5th Edition, CropLife International, Brussels, Belgium.

JMPS 2010, Manual on the development and use of FAO and WHO specifications for pesticides, second revision of first edition, FAO/WHO Joint Meeting on Pesticide Specifications, the Food and Agriculture Organization and World Health Organization of the United Nations, Rome.

OECD, OECD guidelines for testing of chemicals, online publication, Organisation for Economic Cooperation and Development, Paris, France, available on the OECD library.

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